Several devices have been proposed to remove stains or chewing gum and other products such as oil, tar and the like which can form a residue that can adhere stubbornly to outdoor surfaces such as sidewalks, as well as indoors on carpeting or flooring. It is often desired to remove stubbornly adhered products such as discarded chewing gum, particularly in many areas traveled by persons on foot, as in the front of restaurants, pedestrian malls, inside a stadium, or on a busy shopping street. Also, stains on outdoor surfaces or on indoor carpeting also are desirable to be removed.
The present invention provides a self contained and easily maneuverable cleaning machine creating a steamed cleaning solution to be applied to the residue or stain to be removed, but does not require external power and is well balanced so as to be easily portable and capable of use by a single person in a variety of locations.
Chewing gum traditionally has a base of hydrocarbon polymers mixed with sugar and flavorings, and when such gum is chewed, the inner temperature of the mouth results in softening of the gum while the sugar and flavorings are released. The softened base is often discarded onto the ground where it will adhere tightly afterward, and with time the gum residue will often blacken and become rather unsightly. And, as we know, people will often step on discarded gum and carry the gum waste to adhere in another place.
It has been well understood that a heated cleaning agent can be used to remove such gum residue and similar waste; but prior removal devices typically require connection to external power, are cumbersome, and often time consuming to use.
There have been many proposals to remove such waste as chewing gum residue. One such device is disclosed in United Kingdom patent application no. GB 2491661 published Dec. 12, 2012 describing a self contained cleaning apparatus having containers for fuel and cleaning solution to be carried as a backpack or mounted on a trolley. The cleaning solution and fuel are delivered to a wand to be carried by the user wherein the cleaning solution is heated by a gas burner.
Another device, disclosed in U.S. Pat. No. 7,100,540, describes a portable steam and heat generator using a backpack or truck bed for carrying a solution and fuel to be delivered to an applicator wand heating the solution to develop steam by passing the solution through a coiled pipe to be heated. Though not necessarily a steam cleaning device; this device does demonstrate structures attempting to heat a solution quickly, and near the final application of the heated solution.
Similarly, published United States patent applications nos. US 2002/0026954 and US 2011/0232685 disclose cleaning methods and apparati having a hand held wand connected to a separate transport for fuel and cleaning solution.
It has also been proposed to remove residual chewing gum by use of cryogenic or extremely cold gas to spray onto the gum residue to freeze the residue, but it is not easy to move all of the gum residue without undue scrubbing. Also, use of a flame to burn the gum residue has been proposed. Such techniques, however, are not generally safe to use, especially in public places. Use of hot or steaming water with a chemical cleaning agent added has also been proposed, but such devices typically will use a lot of water and may cause unwanted pollution.